Steel rotor for centrifugal pumps.



E. KREHER. STEEL ROTOR FOR UBNTRIFUGAL PUMPS.

T m 9 s m Jm dH 6,3 m ,w a P APPLICATION FILED SEPT. 27, 1910.

WITNESSES B KREHER I STEEL ROTOR FOR OBNTRIPUGAL PUMPS. I

APPLIOATION FILED SEPT. 27, 1910. I L032,287, Patented July 9, 1912.

2 SHEETS-SHEET 2.

INVENTOR II'ZSZE WITNESSES ERNEST .KREHER, or TAMPA, FLORIDA.

STEEL ROTOR FOR GENTRIFUGAL PUMPS. I

Specification of Letters Patent.

Patented July 9, 1912.

Application filed September 27, 1910. Serial No. 584L114.

To all whom it may concern:

' Be it known that I, ERNEST Kain-Inn, a citizen of the United States, residing at Tampa, in the county of Hillsboro and State of Florida, have invented certain new and usesheet metal wherein wear and unbalancing' of the rotor due to the presence of blow holes or defects in castings are avoided. When the rotors of centrifugal pumps have either the blades or side members, or-

both, made of cast metal, the wear incident to the action of the fluid on the pump will tendto expose any blow holes which may be present and then the rotor will become rapidly unbalanced, and because of the high speed at which such rotors are run, this unbalancing of the structure will tend to shake it to pieces. Where angle strips are used to secure the blades to the sides plates, there is always a liability of the rivets working loose with disastrous results.

With the present invention the liabilityof blow holes is completely obviated by making the entire structure where subjected to the action of the fluid being pumped of sheet steel, and for purposes of wear this sheet steel may be of that type known as tool steel, and is, of course, properly tempered.

In order to prevent loosening" of the flights or blades with relation tothe side plates of the rotor, the fastening means are so arranged as to efiectually resist the strains which ordinarily cause the loosening of suchmembers, the relation of these fastening means .to the side plates and blades being such that the directlonof strain does not act upon the fastening means in a manner to cause the loosening thereof.

The invention will be best understood from a consideration of the following detailed description taken in. connection with the accompanying drawings forming a part of this specification, with the understand ing, however, that while the showing of the drawings is that of a practical structure, the proportions and arrangements of parts may be considerably varied from such showing without in any manner departing from the splritiand scope of the invent-ion.

, In the drawings :-Figure 1 is an elevation of the rotor of the pump as viewed from the hub side. Fig. 2 is a similar view with the side plate visible in Fig. 1 removed. Fig. 3 is a section on the llne 33 of Fig.1. Fig. 4 is an elevation of one of the blades or flights separated from the rotor. Fig. 5 is a perspective view of a form of flight which may be employed.

Referring to the drawings, the rotor has two spaced side plates 1, 2, of circular out line, the side plate 1 being madefast to a hub 3, which latter is formed with a concentric exterior ring portion 4: connected to the main body of the hub by a web 5 provided at intervals with perforations 6 matching like perforations 7 in the sidemember or check plate 1, these perforations constituting relief holes. The ring 1 and the side or cheek plate 1 where coincidenttherewith are secured together by rivets 8 of appropriate number and size for the size of the rotor, and other rivets 9 traverse the web 5 and the portion of the cheek plate 1 matching the same. is formed with a passage 10 for receiving a shaft as is customary, but this shaft has been omitted from the drawings, and this body portion of the hub is provided on the inner face with an annular rib 11 against which the inner edge of the cheek-plate 1, which is in fact an annulus, abuts.

It will be observed that the hub 3, together with the ring portion 4, is exterior The body of the hub 3' to the cheek plate 1 except for the small annular rib 11, the inner edge of which, however, does not project beyond the inner face of the cheek plate 1, wherefore the interior of the rotor between the cheek plates is wholly free from any projecting portions of any kind, and is wholly unobstructed ex cept by the blades or flies tobe described.

The side or cheek plate 2 is also an an nu-lus with a central opening 12, larger than the central opening of the cheek plate 1. g The two cheek plates are connected together by blades or fiights13, one of which is shown separately in'Fig. at These blades are appropriately curved and extend from the periphery of the rotor toward the center portion thereof, and their inner ends are beveled, as indicated at 14, thus making one edge of the blade longer than the other, this blade therefore conforming to the opening 12 at its shorter edge and matching the inner diameter of the annulus 1 at the other'edge, so that the inner ends of the assembled blades define a frusto cone,

' cient material to constitute the studs15.

Because of the difference in length of the two edges of the blades, one edge may have more studs 15 formed thereon than the other edge. The cheek plates 1 and 2 are provided with appropriate passages for receiving the studs 15, and these passages may be counter-sunkat their outer ends so that ,the studs may be headed or upset therein to form rivet connections between the blades 13 and the side or cheek plates. 1 and 2. The blades 13 therefore constitute the junction members for the cheek plates and the rivets are integral with these cheek plates,

' to loosen the rivet connections to the ultimate destruction of the'rotor.

Instead of forming the studs 15 on the edges of the blades 13' where they engage the cheek plates, such edges may *be turned at an angle and the flanges so formed may be perforated for the passage of rivets ex- 1 tending through appropriate holes in the Check plates. .ySucha bladeis shown at 13 in Fig, 5, and the flanges are indicated at; 16 in the same. figure, while the rivet holes in these flanges are indicated at' 17. The flanges are integral with the body of the blade and here again the principal forces acting on therivets are those tending to shear the rivets and not elongate or loosenl" them. I v

No casting is assuredly free from blow holes, while many castings contain them. For this reason rotors of the general character to which this invention relates are comparatively short lived, since the unbalancing of the rotor due to the presence of blow holes sets up vibrations ultimately destructive to the structure.

In a rotor madewholly of sheet metal so far as the active portions are concerned, there is an entire absenceof blow holes and consequently the rotor may be made well balanced with the assurance that this balance will be maintained indefinitely and the life of the rotor is correspondingly prolonged. Furthermore, the superior strength of sheet metal, weight for weight, makes it possible to build the. rotors of materially lighter weight than a cast rotor of the same strength.

Moreover, since the blades or flights may .be made quite thin when constructed'of sheet metal as compared with like blades or flights of cast metal, the capacity of the pump is. materially increased.

VVhat is claimed is p 1. A rotor for pumps comprising two plane sheet "metal cheek plates of the same external diameter with central passages therethrough of respectively different diameters, a hub to which,the cheek plate having the passage of small diameter is directly secured, said hub being located wholly outside the plane of the inner face of the cheek plate it carries, and a single circular series of curved flies'or blades constituting the sole part-s within the space between'the inner "walls of the cheek plates, said curved flies or blades having their outer ends sub stantiallycoihcidentwith the periphery of thetrotor and their inner ends beveled in the direction of the axis of rotation of the rotor into substantial conformity with the openings through the cheek plates, said'flies having integral studs on opposite sides thereof, and the cheek plates having perforations matching the studs and into which the studs project and are there riveted.

2. A rotor for pumps comprising two plane sheet metal cheek plates of the same external diameter with central passages therethrough of respectively different diameters, a hub towhich the cheek plate having the passage of small diameter is directly secured, said hub beinglocated wholly outside the plane of the innerface of the cheek plate it carries, and a single circular series of curved flies or blades constituting the sole parts within the space between the inner walls of the cheek plates, said curved flies or blades havingtheir outer ends substantially coincident with the periphery of the rotor and their inner ends beveled in the direction a of the axis of rotation of the rbtor into substantial conformity with the openings through the cheek plates, said flies having integral studs on opposite sides thereof, and

.the cheek plates having perforations matching the studs and into which the studs 'project and are there riveted, the hub "being provided with an annular portion connecte to the main body of the hub by a web withpassages therethrough andthe cheek plate 5 carried by the hub having passagesthrough it matching the passages through the webof the hub.

V In testimony whereof I have vaifizaced my signature in presence of two witnesses.

I ERNEST KREHER.

Witnesses:

JosEP'mNE CARROLL,

0. Farm THOMPSON. 

